For effective improvement the safety of the padlock to further protect the rights and interests, most of the industrial businessmen eagerly endeavor the research and development in the structural improvement of the padlock resulting into the current combination padlock from the evolution of non-combination padlock in the early stages. Other than the common combination padlock, some patented combination padlock with features of anti-vandal trait and easiness of operation are presented to the public in succession.
Please refer to the FIGS. 1 and 2 for the perspective exploded view and the facade cross section view of the conventional padlock, which comprises a lock body 10, a core 20, a triangular pad 30, a locking claw 40 and an U-shaped locking shackle 50, wherein,
said lock body 10, which configures a cavity well 101, has a pair of retaining holes 102 formed in the top surface and a pair of latching lumps 103 formed adjacent to the bottom section of the retaining holes 102;
said core 20, which located inside of the cavity well 101 with a pair of upper escutcheons 201 and a pair of lower escutcheons 202 attached thereon, has a shaft 203 and mating bushing collar 204 running through plural sets of numerical dial wheels 205 and coupling tumbler cams 206 in between straddled over the pair of lower escutcheons 202 as well as a triangular pad 30 and a rocking claw 40 inserted between the pair of upper escutcheon 201;
said triangular pad 30, which is inserted between the pair of upper escutcheon 201 in the core 20, serves as a supporting base for the locking claw 40 to enhance stability;
said rocking claw 40, which straddles over the pair of upper escutcheons 201 in the core 20 by its fulcrum arm 402 for rocking to and fro, has a latching lever 401 extended between the latching lumps 103 of the lock body 10, plural pawls 403 extended downwards to press over corresponding tumbler cams 206, a blocking dog 404 extended to act with the corresponding bushing collar 204 and a clipping spring 405 disposed at front side thereof; and
said locking shackle 50, whose short arm and elongated arm are engaged in the pair of retaining holes 102 of the lock body 10, has a clasping indentation 501 created at each arm to catch with each corresponding latching lump 103, and an anchor terminal 503 being coiled with restoring spring 502 extended over the end of the elongated arm.
For operation to the “locked status” reflecting the discrepancy of the combination in numerical dial wheels 205 to the preset correct combination, the bulging curve of at least one tumbler cam 206 will push the corresponding pawl 403 of the rocking claw 40 outwardly (as shown in the FIG. 3) so that the pair of the latching lumps 103 are reactively stretched to latch in the pair of corresponding clasping indentations 501 of the locking shackle 50 owing to the latching lever 401 of the rocking claw 40 will be inwardly seesawed by the pawl 403 in between the pair of the latching lumps 103.
Conversely, for operation to the “unlocked status” reflecting the consistence of the combination in numerical dial wheels 205 with the preset correct combination, the planar face of all tumbler cams 206 will retracted the corresponding pawl 403 of the rocking claw 40 inwardly by the clipping spring 405 (as shown in the FIG. 4) so that the pair of the latching lumps 103 are reactively released to free from the pair of corresponding clasping indentations 501 of the locking shackle 50 owing to the latching lever 401 of the rocking claw 40 will be outwardly seesawed by the pawl 403 out of the pair of the latching lumps 103; thus, the locking shackle 50 is freed to slide away the retaining holes 102 of the lock body 10 by the rebound of restoring spring 502.
For operation to alter the correct combination reset, it should be performed under the unlocked status for the conventional padlock that namely the anchor terminal 503 of the locking shackle 50 should not block the bushing collar 204 and the blocking dog 404 of the rocking claw 40 should not intervene between the bushing collar 204 and lower escutcheon 202. However, the redundant description will be neglected here as this beyond the scope of the disclosure for the present invention. Basing on the description heretofore together with the experimental observation, the rocking claw 40 of the conventional padlock has critical instable drawback because it simply straddles over the upper escutcheons 201 by its fulcrum arm 402 though being further supported by the triangular pad 30.
Moreover, the locked status and unlocked status of the conventional padlock depends on the rocking status of the rocking claw 40. In other words, the padlock is in unlocked status as long as the latching lever 401 of the rocking claw 40 does not locate between the latching lumps 103. Accordingly, the vandal people can easily unlock the conventional padlock via studying in know-how of releasing or breaking the latching lever 401 from the latching lumps 103 without knowledge of the correct combination preset. From practical observation on the phenomenon aforesaid for many years, two popular vandal methods adopted are that forcefully pry and ruin the rocking claw 40 by inserting the tapering flat tool into the gap between the adjacent numerical dial wheels 205, or forcefully loose and fall apart the rocking claw 40 by directly beating the numerical dial wheels 205 with hammer or the like. That is the safety drawback of the conventional padlock need to be improved. Realizing and addressing these facts and drawbacks mentioned above for the conventional padlock, the applicant is eager to improve and solve these issues. Through hard research and development as well as test and improvement, eventually, the present invention is successful developed.